Thermal stability of perfluoroalkyl silane self-assembled on a polycrystalline aluminum surface

Thermal stability behavior of 1H, 1H,2H,2H-perfluorooctyl trichlorosilane self-assembled on aluminum substrates is characterized using a grazing-angle Fourier transform infrared spectrometer, Fourier transform-Raman spectroscopy, and contact angle measurements. The self-assembled monolayer (SAM) is...

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Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 20(2004), 4 vom: 17. Feb., Seite 1329-34
1. Verfasser: Devaprakasam, D (VerfasserIn)
Weitere Verfasser: Sampath, S, Biswas, S K
Format: Aufsatz
Sprache:English
Veröffentlicht: 2004
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article
Beschreibung
Zusammenfassung:Thermal stability behavior of 1H, 1H,2H,2H-perfluorooctyl trichlorosilane self-assembled on aluminum substrates is characterized using a grazing-angle Fourier transform infrared spectrometer, Fourier transform-Raman spectroscopy, and contact angle measurements. The self-assembled monolayer (SAM) is heated quasi-statically from room temperature to above 633 K with a heating rate of 1 K/s. Variations in peak frequencies, integrated areas of intensities of symmetric and antisymmetric CF2 stretches, and the relative tilt angle of the SAM are reported. We find that the conformational order in the SAM is not disrupted because of thermal cycling when the peak temperature is below 423 K. When the peak temperature is between 423 and 603 K, the cycling results in only a partial retention of the original order. When the peak temperature is above 603 K, the process is completely irreversible. Surface-enhanced Raman spectroscopy and contact angle measurements support these observations. We confirm these trends for a longer chain (1H,1H,2H,2H-perfluordecyl trichlorosilane) molecule of the same family using the same techniques. We discuss the possible reasons for the changes in light of the tilting-untilting and uncoiling-coiling of the helical silane monolayer
Beschreibung:Date Completed 26.01.2006
Date Revised 26.10.2019
published: Print
Citation Status PubMed-not-MEDLINE
ISSN:1520-5827